Platform assembly for a multiple chain pair transport device

ABSTRACT

As described herein, a platform for a multiple chain pair transport device includes a plurality of spaced rigid linear members coupled at their ends to selected chain pairs and a plurality of selectively flexible interconnecting members. The interconnecting members are arranged in a grid pattern between the chain pairs and include spaced pairs of complementary shaped locking members. The locking members comprise overlapping portions that are relatively rotatable through a predetermined arc and are supported by and spaced between the rigid linear members. The overlapping portions include matching arcuate keyways and protrusions which permit the locking members to flex upwardly and to be rigidly locked in a horizontal position in response to loads bearing downwardly against the support members.

Schatte 1 Nov. 13, 1973 PLATFORM ASSEMBLY FOR A MULTIPLE CHA1N PAIR TRANSPORT DEVICE [l 5 Inventor: Kurt Schatte,HopewellJunction,

Primary Examiner-Evon CL Blunk Assistant Examiner-Douglas D. Watts Attorney-Granville Brumbaugh et a1.

[5 7] ABSTRACT As described herein, a platform for a multiple chain pair transport device includes a plurality of spaced rigid linear members coupled at their ends to selected chain pairs and a plurality of selectively flexible interconnecting members. The interconnecting members are arranged in a grid pattern between the chain pairs and include spaced pairs of complementary shaped locking members. The locking members comprise overlapping portions that are relatively rotatable through a predetermined arc and are supported by and spaced between the rigid linear members. The overlapping portions include matching arcuate keyways and protrusions which permit the locking members to flex upwardly and to be rigidly locked in a horizontal position in response to loads bearing downwardly against the support members.

3 Claims, 5 Drawing Figures PATENIEUNUY 13 1915 3.771.. 642

SHEET 1 or 2 PLATFORM ASSEMBLY FOR A MULTIPLE CHAIN PAIR TRANSPORT DEVICE BACKGROUND OF THE INVENTION This invention relates to platform assemblies and, more particularly, to platform assemblies for use in transport devices of the multiple chain pair type.

In the recently issued U.S. Pat. No. 3,578,145, licensed to the assignee of the present invention, there is disclosed a multiple chain pair transport device that represents a totally new and unique development in the field of lift and transport devices. In connection with such multiple chain pair transport device, there is provided a platform that effectively comprises a plurality of independent platforms connected at their ends to selected chain pairs which move together to form one platform. The multiple narrow platforms move together during horizontal and vertical movement and simply breakup into units when the chains go around the drive and guide sprockets.

This unique feature of the foregoing platform assembly makes it possible to combine many lifting and transporting units into one continuous system, and combining numberous vertical and horizontal movement into one continuous flow, notwithstanding the direction of movement. Furthermore, by virtue of the multiple chain pair configuration of the transport device and the multiple platform construction of the platforms, the load carrying capability of the device is vastly improved. This improvement is due to the even distribution of the load throughout the platform.

In an application entitled A Platform Assembly for Multiple Chain Transport Device, filed June I, 1971, Ser. No. 148,385, and assigned to the assignee of the present invention, there is disclosed one specific form of a platform for use in a transport device of the multiple chain pair type. This devices includes a plurality of spaced rigid linear members coupled at their ends to selected chain pairs and a plurality of support members which span the distance between the chain pairs. Selected support members are secured to the spaced rigid linear members and supported thereby, and'the support members have double-barreled' configurations with keyways formed therein. Successive support members include overlapping portions that are hinged together by pin members which permit the support members to flex upwardly in the absence of a load bearing thereagainst and to be rigidly locked in horizontal position in response to loads bearing downwardly against the support members.

The foregoing type platform is extremely effective and will carry unit loads of material without limitation as to the size of the unit loads of material. However, the number and size of the elements forming the platform can make the platforms expensive to manufacture and assemble. In some installations, the use to which the transport device is put will not justify the cost of such paltforms.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a platform for multiple chain pair transport devices that is inexpensive to manufacture and assemble and, yet carry unit loads of material virtually without limitation as to the size of the unit loads of material.

It is a further object of the present invention to provide a platform comprising in combination the multiple independent platform members disclosed in U.S. Pat. No. 3,578,145, and a plurality of selectively flexible interconnecting members that form a grid pattern spanning the length and width of the platform formed by the multiple platform members.

These and other objects of the present invention are accomplished by the platform of the present invention which comprises a first plurality of spaced rigid linear members, each member being connected at its ends to one pair of a plurality of pairs of offset and movable endless flexible support members and a plurality of selectively flexible interconnecting members. The interconnecting members are arranged in a grid pattern between the chain pairs and include spaced pairs of complementary shaped locking members. The locking members comprise overlapping portions that are relatively rotatable through a predetermined arc and are supported by and spaced between the rigid linear members.

In a preferred embodiment, the overlapping portions include matching arcuate keyways and protrusions which permit the locking members to flex upwardly and to be rigidly locked in a horizontal position in re sponse to loads bearing downwardly against the support members.

BRIEF DESCRIPTION OF THE DRAWINGS In the Drawings:

FIG. 1 is a top plan view of a platform assembly for a four chain pair transport device arranged according to the present invention;

FIG. 2 is a sectional view of the platform assembly of the present invention taken along line 2-2 of FIG. I and looking in the direction of the arrows;

FIG. 3 is an enlarged fragmentary top plan view of the platform assembly of the present invention;

FIG. 4 is a sectional view of the platform assembly of the present invention taken along line 4-4 of FIG. 3; and

FIG. 5 is a sectional view of the platform assembly taken along line 5--5 of FIG. 4 and looking in the direction of the arrows.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I, there is shown a perspective view of a transport device It), with a platform assembly of the type disclosed in the U.S. Pat. No. 3,578,l45,'and comprising four pairs of chains of the type disclosed in the U.S. Pat. No. 3,358,550, which is also licensed to the assignee of the present invention. In particular, the transport device 10 comprises four chain pairs 12, 14, 16 and 18 that are driven and guided in prescribed endless loops by drive and guide members (not shown), such as sprockets. The chain pairs l2, 14, 16 and 18 comprise laterally spaced chains 12a, 12b; 14a, 14b; 16a, 16b; and 18a, 18b, respectively. Because of the configuration of the chains only two of the four chain pairs are offset. Specifically, the chains 12a, b a and 12b, 18b, are arranged to interlock and thereby move in the same plane and over the same sprockets. Simibetween the chain pairs 12 and I8. Thus, the chain pairs 12 and 18 may be referred to as the inner chain pairs and the pairs 14 and 16 may be referred to as the outer chain pairs. For a more detailed disclosure of the construction and operation of chain drive systems comprising chains of the type shown in FIG. 1, reference may be made to the U.S. Pat. No. 3,583,550.

As shown in FIG. 1, the longitudinal distance between the chain pairs 12 and 18 is determinative of the required longitudinal extent of a load carrying platform which is conveyed by the chain pairs l2, 14, 16 and 18. In particular, a platform 20 is provided which includes four tube members 21, 22, 23 and 24 which are attached to the chains 12a, 12b; 14a, 14b; 16a, 16b; and 18a, 18b, respectively, through load carrying rollers 21a, 21b; 22a, 22b; 23a, 23b and 24a, 24b, respectively. In order to provide a platform having a uniform lateral dimension, load carrying rollers 22a, 22b and 23a, 23b which affix the bars 22 and 23 to the outer chain pairs 14 and 16 are located inwardly of the chain pairs 14 and 16 to a greater extent than are the rollers 21a, 21b and 24a, 24b spaced from the chain pairs 12 and 18. As described in detail in the U.S. Pat.

No. 3,578,145, sets of offset and stationary lateral and vertical guides may be mounted on the frame that supports the chain pairs and related accessory equipment. The rollers 21a, 21b; 22a, 22b; 23a, 23 b; and 24a, 24b are adapted to travel in the guides, the guides providing support for the chain pairs 12, 14, 16 and 18 and reducing lateral vibration between the chain pairs.

In accordance with the present invention, there is shown in the drawings a unique and novel platform assembly 30 that is particularly adapted for a multiple chain pair transport device of the type described above and in US. Pat. No. 3,578,145. As best shown in FIGS.

2-5, the platform assembly 30 includes rows 32-41 of overlapping figure eight-shaped interlocking members 32a, 32b; 33a, 33b; 34a, 34b; 35a, 35b; 36a, 36b; 37a, 37b; 38a, 38b; 39a, 39b; 40a, 40b; and 41a, 41b, respectively. The interlocking members overlap at opposite ends whereby the openingsin such opposite ends are aligned.

The aligned openings of the endmost and intermediate a and b interlocking members receive the tube members 21, -22, 23 and 24 forming the basic platform. Intermediately disposed tube members 42-46, 47-51 and 52-55 span the width of the platform and extend through and support the remaining a and b interlocking members to complete the platform.

As best shown in FIGS. 4 and 5, the two openings in each of the interlocking members include arcuate keyways 56 formed at the extreme ends thereof. The keyways formed in the a interlocking members are identifled by the number 56a and the keyways formed in the b interlocking members are identified by the number 56b. The two openings in each of the interlocking members include inwardly extending protrusions 58 formed in the surface of the members angularly of the keyways 56. The protrusions 58 formed in the a interlocking members are identified by the number 58a and the protrusions formed in the b interlocking membets are identified by the number 58b.

When the openings in the opposite ends of the a and b interlocking members are aligned and their inner surfaces arranged in abutting relationship, the protrusions 58a of the a members fit into the keyways 56b of the b members and the protrusions 58b of the b members fit into the keyways 56a of the a members. As shown in FIG. 4, this arrangement will allow the a and b members to rotate relative to one another through an arc of approximately The extent of the arc is defined by the angular distance of the keyways 56.

The effective operation of the interlocking a and b support members is dependent upon the maintenance of an abutting relationship between the support members. To this end, the a and b support members are mounted on the tubes 21-24 and 42-55, as shown, and washers 60a and 60b are pressed against the interlocking support members and then welded to the tubes. The washers 60a and 60b preclude longitudinal movement by the interlocking a and b support members along the tubes and keep the protrusions of a and b members fitted into the corresponding keyways of their corresponding overlapping a and 5 members.

In light of the foregoing, it will be seen that in operation the interlocking a and b members can bend downwardly from a horizontal plane until the protrusions 58a and 58b reach the lowermost edges of the keyways 56b and 56a respectively. The downward deflection by the support members is precluded by the engagement between the protrusions 58a and 58b and the uppermost edges of the keyways 56b and 56a, respectively. Thus, the platform 30 is unidirectionally flexible, i.e., in the upper direction, which enables it to bend around and under sprockets, as the case may be, as the platform is conveyed between its unloading and loading positions. It is in this return flow path where platform flexibility is required and the configuration of the platform of the present invention provides the requisite flexibility. On the other hand, the platform 30 is maintained flat and inflexible as the platform is conveyed from the location where unit loads of material are deposited onto the platform to the location where the unit loads of material are unloaded.

Still further, the tube members 21, 22, 23 and 24 carry the platform 30 and full advantage is taken of increased load carrying capability provided by the plurality of chain pairs 12, 14, 16 and 18, as described in the US. Pat. No. 3,578,145. The a and b interconnecting members form a grid pattern spanning the length and width of the platform formed by the tube members. The size and spacing of the a and b members can be modified to vary the grid pattern to accommodate unit loads of varying sizes. In particular, the grid pattern may be opened up where the platform is to carry larger loads and closed or compressed where the platform is to carry smaller loads.

Although the invention has been described herein with reference to a specific embodiment, many modifications and variations therein will readily be apparent to those skilled in the art. Accordingly, all such variations and modifications are included within the intended scope of the invention as defined by the following claims.

I claim:

1. In a platform assembly for a multiple chain pair transport device having a plurality of spaced rigid linear members coupled at their ends to selected chain pairs, the improvement comprising a plurality of selectively flexible interconnecting members arranged in a grid pattern between the chain pairs, the interconnecting members comprising spaced pairs of complementary shaped locking members arranged in abutting relationship, the locking members having overlapping portions rotatable through a predetermined arc and supported by selected ones of the rigid linear members and free end portions supported respectively by two other spaced rigid linear members, the locking members further having openings formed in the ends thereof and angularly spaced arcuate cutouts and protrusions formed therein radially outwardly of the openings, the locking members overlapping at opposite ends whereby the openings in such opposite ends are aligned and the protrusions of each locking member projecting from a plane of the locking member and being configured to fit into the cutouts of other locking members to permit relative rotational movement therebetween.

2. A platform assembly according to claim 1 wherein the cutouts and protrusions formed in the locking members are arranged to permit the free ends of the members to bend downwardly from a horizontal plane, but to preclude the downward deflection by the overlapping portions.

3. A platform assembly according to claim 3 further comprising groups of spaced rigid linear members mounted respectively between and coextensive with the linear members coupled at their ends to the chain pairs, and spaced rows of locking members having overlapping portions coupling the linear members together and to the linear members coupled at their ends to the chain pairs. 

1. In a platform assembly for a multiple chain pair transport device having a plurality of spaced rigid linear members coupled at their ends to selected chain pairs, the improvement comprising a plurality of selectively flexible interconnecting members arranged in a grid pattern between the chain pairs, the interconnecting members comprising spaced pairs of complementary shaped locking members arranged in abutting relationship, the locking members having overlapping portions rotatable through a predetermined arc and supported by selected ones of the rigid linear members and free end portions supported respectively by two other spaced rigid linear members, the locking members further having openings formed in the ends thereof and angularly spaced arcuate cutouts and protrusions formed therein radially outwardly of the openings, the locking members overlapping at opposite ends whereby the openings in such opposite ends are aligned and the protrusions of each locking member projecting from a plane of the locking member and being configured to fit into the cutouts of other locking members to permit relative rOtational movement therebetween.
 2. A platform assembly according to claim 1 wherein the cutouts and protrusions formed in the locking members are arranged to permit the free ends of the members to bend downwardly from a horizontal plane, but to preclude the downward deflection by the overlapping portions.
 3. A platform assembly according to claim 3 further comprising groups of spaced rigid linear members mounted respectively between and coextensive with the linear members coupled at their ends to the chain pairs, and spaced rows of locking members having overlapping portions coupling the linear members together and to the linear members coupled at their ends to the chain pairs. 